Midazolam, the most frequent sedative, is a benzodiazepine with hypnotic and sedative effects (2). The half-life of the substance is about 1-2.5 hours, and thus substantially longer than the duration of a colonoscopy (approximately 30 minutes). Additionally, Midazolam gives pronounced amnesia that lasts even longer than the hypnotic effect. Opioids are also frequently used during colonoscopy, with Pethidine as the most common one (half-life: 3 hours).